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NacNac
NacNac is a class of anionic bidentate ligands. 1,3-Diketimines are often referred to as "HNacNac", a modification of the abbreviation Hacetylacetone, acac used for 1,3-diketones. These species can exist as a mixture of tautomers. Preparation of ligands and complexes Acetylacetone and related 1,3-diketones Condensation reaction, condense with primary alkyl- or arylamines resulting in replacement of the carbonyl oxygen atoms with NR groups, where R = aryl, alkyl. To prepare 1,3-diketimines from Steric effects, bulky amines, e.g. 2,4,6-Trimethylaniline, 2,4,6-trimethylanilines, prolonged reaction times are required. 2,6-Diisopropylaniline is a common bulky building block. Deprotonation of HNacNac compounds affords anionic bidentate ligands that form a variety of coordination complexes. Some derivatives with large Side chain, R groups can be used to stabilize low valent p-block, main group and transition metal complexes. Unlike the situation for the acetylacetonates, the steric pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylacetone
Acetylacetone is an organic compound with the chemical formula . It is classified as a 1,3-diketone. It exists in equilibrium with a tautomer . The mixture is a colorless liquid. These tautomers interconvert so rapidly under most conditions that they are treated as a single compound in most applications. Acetylacetone is a building block for the synthesis of many coordination complexes as well as heterocyclic compounds. Properties Tautomerism The Keto–enol tautomerism, keto and enol tautomers of acetylacetone coexist in solution. The enol form has C2v molecular symmetry, symmetry, meaning the hydrogen atom is shared equally between the two oxygen atoms. In the gas phase, the equilibrium constant, ''K''keto→enol, is 11.7, favoring the enol form. The two tautomeric forms can be distinguished by NMR spectroscopy, IR spectroscopy and other methods. The equilibrium constant tends to be high in nonpolar solvents; when ''K''keto→enol is equal or greater than 1, the enol form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,6-Diisopropylaniline
2,6-Diisopropylaniline is an organic compound with the formula H2NC6H3(CHMe2)2 (Me = CH3). It is a colorless liquid although, like many anilines, samples can appear yellow or brown. 2,6-Diisopropylaniline is a bulky aromatic amine that is often used to make ligands in coordination chemistry. The Schrock carbenes often are transition metal imido complexes derived from this aniline. Condensation with diacetylpyridine and acetylacetone gives, respectively, diiminopyridine and NacNac NacNac is a class of anionic bidentate ligands. 1,3-Diketimines are often referred to as "HNacNac", a modification of the abbreviation Hacetylacetone, acac used for 1,3-diketones. These species can exist as a mixture of tautomers. Preparation of ... ligands. left, 220px, Typical Schrock-style spectator_ligand.html" ;"title="olefin metathesis catalysts feature bulky imides as spectator ligand">olefin metathesis catalysts feature bulky imides as spectator ligands. References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylacetone
Acetylacetone is an organic compound with the chemical formula . It is classified as a 1,3-diketone. It exists in equilibrium with a tautomer . The mixture is a colorless liquid. These tautomers interconvert so rapidly under most conditions that they are treated as a single compound in most applications. Acetylacetone is a building block for the synthesis of many coordination complexes as well as heterocyclic compounds. Properties Tautomerism The Keto–enol tautomerism, keto and enol tautomers of acetylacetone coexist in solution. The enol form has C2v molecular symmetry, symmetry, meaning the hydrogen atom is shared equally between the two oxygen atoms. In the gas phase, the equilibrium constant, ''K''keto→enol, is 11.7, favoring the enol form. The two tautomeric forms can be distinguished by NMR spectroscopy, IR spectroscopy and other methods. The equilibrium constant tends to be high in nonpolar solvents; when ''K''keto→enol is equal or greater than 1, the enol form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chem Structure Of Hnacnac , a place in Finland
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Chem may refer to: *Chemistry *Chemical * ''Chem'' (journal), a scientific journal published by Cell Press *Post apocalyptic slang for "drugs", medicinal or otherwise in the Fallout video game series. In Ancient Egyptian usage: * ''Khem'' (also spelt ''Chem''), the Egyptian word for "black" *Min (god), in the past erroneously named ''Khem'' CHEM may refer to : *A metabolic panel: for instance, CHEM-7, which is the basic metabolic panel *CHEM-DT, a Canadian television channel See also *Chemo (other) *Kem (other) *Kemi Kemi (; ; ; ) is a cities of Finland, town and municipalities of Finland, municipality of Finland. It is located approximately from the city of Tornio and the Finland–Sweden border, Swedish border. The distance to Oulu is to the south and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-block
A block of the periodic table is a set of elements unified by the atomic orbitals their valence electrons or vacancies lie in. The term seems to have been first used by Charles Janet. Each block is named after its characteristic orbital: s-block, p-block, d-block, f-block and g-block. The block names (s, p, d, and f) are derived from the spectroscopic notation for the value of an electron's azimuthal quantum number: sharp (0), principal (1), diffuse (2), and fundamental (3). Succeeding notations proceed in alphabetical order, as g, h, etc., though elements that would belong in such blocks have not yet been found. Characteristics There is an ''approximate'' correspondence between this nomenclature of blocks, based on electronic configuration, and sets of elements based on chemical properties. The s-block and p-block together are usually considered main-group elements, the d-block corresponds to the transition metals, and the f-block corresponds to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligands
In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Complexes
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the periodic table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reviews
''Chemical Reviews'' is peer-reviewed scientific journal published twice per month by the American Chemical Society. It publishes review articles on all aspects of chemistry. It was established in 1924 by William Albert Noyes (University of Illinois). The editor-in-chief is Sharon Hammes-Schiffer. Abstracting and indexing The journal is abstracted and indexed in Chemical Abstracts Service, CAB International, EBSCOhost, ProQuest, PubMed, Scopus, and the Science Citation Index. According to the ''Journal Citation Reports'', the journal has a 2023 impact factor of 51.4. Journal ranking summary Based on the latest announced rankings, ''Chemical Reviews'' is positioned among the top journals in the field of chemistry across multiple citation databases. The following table summarizes its performance across Scopus and Web of Science. Journal ranking summary (2023)JRank: Chemical Reviewshttps://jrank.net/journals/chem-rev/metrics/ref> See also * Accounts of Chemical Research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Side Chain
In organic chemistry and biochemistry, a side chain is a substituent, chemical group that is attached to a core part of the molecule called the "main chain" or backbone chain, backbone. The side chain is a hydrocarbon branching element of a molecule that is attached to a larger hydrocarbon backbone. It is one factor in determining a molecule's properties and reactivity. A side chain is also known as a pendant chain, but a pendant group (side group) has a different definition. Conventions The placeholder R is often used as a generic placeholder for alkyl (saturated hydrocarbon) group side chains in structural formulae. To indicate other non-carbon groups in structure diagrams, X, Y, or Z are often used. History The ''R'' symbol was introduced by 19th-century French chemist Charles Frédéric Gerhardt, who advocated its adoption on the grounds that it would be widely recognizable and intelligible given its correspondence in multiple European languages to the initial letter of "r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organometallics
''Organometallics'' is a biweekly journal published by the American Chemical Society. Its area of focus is organometallic and organometalloid chemistry. This peer-reviewed journal has an impact factor of 3.837 as reported by the 2021 Journal Citation Reports by Thomson Reuters. Since 2015 Paul Chirik is the editor-in-chief of ''Organometallics''. He is an American chemist and the Edwards S. Sanford Professor of Chemistry at Princeton University, and associate director for external partnerships of the Andlinger Center for Energy and the Environment. He writes about the catalysis of hydrocarbons. Past editors-in-chief are Dietmar Seyferth and John Gladysz. Retrieved on 2014-07-30. This journal is indexed in |
Transition Metal
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. The lanthanide and actinide elements (the f-block) are called inner transition metals and are sometimes considered to be transition metals as well. They are lustrous metals with good electrical and thermal conductivity. Most (with the exception of group 11 and group 12) are hard and strong, and have high melting and boiling temperatures. They form compounds in any of two or more different oxidation states and bind to a variety of ligands to form coordination complexes that are often coloured. They form many useful alloys and are often employed as catalysts in elemental form or in compounds such as coordination complexes and oxides. Most are strongly paramagnetic because of their unpaired d electrons, as are many of their compounds. All of the elements that are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
